This section is intended to provide a background or context to the invention that is recited in the claims. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
Certain abbreviations that may be found in the description and/or in the Figures are herewith defined as follows:    CBS Citizens Band Radio    ESPRIT Estimation of Signal Parameter via Rotational Invariance Technique    FCC Federal Communications Commission    FNPRM Further Notice of Proposed RuleMaking    LTE Long Term Evolution    MUSIC Multiple Signal Classifier    SON Self Organizing Network
On Apr. 23, 2014 the Federal Communications Commission (FCC) adopted a Further Notice of Proposed Rulemaking (FNPRM)/Further Consultation aimed at using spectrum sharing techniques to make more spectrum available for wireless broadband services in 3550-3650 MHz also referred to as the 3.5 GHz band hereafter. The spectrum would be available for small-cell and other types of deployments.
The FCC considers this band to be an opportunity to test innovative spectrum-sharing techniques, which could later be extended to other spectrum bands. Access and operation would be managed to avoid interference with existing users of the spectrum by a Spectrum Access System, which is described as a dynamic database that incorporates technical and functional requirements to manage access and operations on the spectrum. It is to be noted that while 3550-3650 MHz is the initial major band for spectrum sharing in the USA, other spectrum bands are expected to follow such as 3100-3550 MHz. In other countries, similar spectrum sharing scenarios could occur in various bands. In this disclosure overcoming interference caused by incumbent spectral users like radar systems in a shared spectrum is addressed.